This invention relates generally to image processors of the type which are located on the focal plane of an imaging array.
The focal plane processor is an image processor which is incorporated into the focal plane. The focal plane is the light sensitive circuit on which the optical array focuses ambient light. An imaging array captures an image which strikes an array of pixel sensors lying on the focal plane. The pixel sensors convert light into electrical signals. Generally, the focal plane is defined by the surface of a semiconductor device which has plurality of light sensitive elements formed thereon to achieve a pixel sensing capability.
While conventional optical pixel sensors have used charged coupled devices (CCD's) and many modern commercial devices use this technology, it has been appreciated that the application of complementary metal oxide semiconductor CMOS technology to imaging sensors could result in an imaging sensor with on-chip computational capabilities. Thus, it has been appreciated that an imaging array could be made on the same process technology as a processor and the two functions, which typically are implemented on separate semiconductor chips, could be incorporated into a single chip. This would offer a number of important advantages including low cost and potentially high computational speed.
Traditionally, imagers include an integrated circuit which receives an electrical signal indicative of the intensity value of the incident radiation. The circuit passes these intensity values on for subsequent image processing. The image processor is typically a digital signal processor which allows various image processing operations to occur. The digital signal processor may in turn be coupled to a microprocessor.
Typically, a relatively small imaging array is utilized for cost reasons. The captured image may then be scaled upwardly in size by interpolating additional intensity values between the actual intensity values determined by the pixel sensors. The more interpolated values that are utilized, the larger the resulting scaled picture. In this way a relatively low cost imaging system may be utilized to achieve a relatively large-sized output display.
Traditionally scaling is done by external computers which are coupled to the image processor. This added computational capability increases the cost of the imaging system.
Thus, there is a continuing need for a low cost imager which provides advanced imaging functions.